Apple's iOS and Google's Android operating system, the vaunted "duopoly" of the smartphone market, accounted for nine out of 10 smartphones sold worldwide in the fourth quarter of last year, about the same as its total market share for 2012, according to data released on Thursday.

International Data Corp.'s report found that 70 percent of phone shipments in the quarter were devices powered by Android, made by a range of manufacturers, while 21 percent were iPhones.

BlackBerry Slips

Most of the remainder were BlackBerry devices (3.2 percent), those powered by Microsoft Windows Phone (2.6 percent) and Linux, used by NEC, Panasonic and others, at 1.7 percent.

BlackBerry (formerly Research In Motion) saw the biggest loss in market share, from its 8.1 percent share in the fourth quarter of 2011 to 3.2 percent. Windows grew from 1.5 percent to 2.6 percent during the same period.

Android devices ruled the roost in overall market share, with 68.8 percent of the market, up from 49.2 percent the previous year. Apple's iPhones kept the same market share, 18.8 percent, but saw a huge bump in shipments, from 93 million to nearly 136 million.

Android's shipments for the year grew 243 million to 497 million, however.

"The dominance of Android and Apple reached a new watermark in the fourth quarter," said Ramon Llamas, research manager with IDC's Mobile Phone team, in a press statement.

"Android boasted a broad selection of smartphones, and an equally deep list of smartphone vendor partners. Finding an Android smartphone for nearly any budget, taste, size and price was all but guaranteed during 2012. As a result, Android was rewarded with market-beating growth."

There was strong demand for the iPhone 5, released during the fourth quarter, he added, while lower prices on the older iPhone 4 and 4S made the iOS platform more accessible to new users.

The biggest loser of 2012 was the Symbian platform, abandoned by Nokia in favor of Windows Phone and now being phased out. Its market share plunged from 16.5 percent to just 3.3 percent, while shipments dropped from more than 81 million to just under 24 million.

Framingham, Mass.,-based IDC's numbers are based on its research from vendors and other sources in more than 100 countries around the globe, the company says.

Business Base vs. Deep Pockets

Windows Phone devices, particularly Nokia's Lumia, have proven popular in the important U.S. market, driving the platform to third place here, according to a recent report by Strategy Analytics. The coming months will see it in a pitched battle with BlackBerry, with its newest OS, for increased share, analysts agree.

"[The duopoly] should not change for another year or two as both [top] platforms will only entrench their already solid position," said Kirk Parsons, a wireless analyst with J.D. Power and Associates. "It would be hard to predict how BB10 or Windows 8 will fare in the marketplace -- RIM has a much bigger base so that could be their saving grace, while Microsoft has the deep pockets."